Driving and locking mechanism for a threaded bearing cup

ABSTRACT

A differential allowing relatively easy alignment and secure positioning of bearings is provided. The differential includes a differential carrier and a differential case disposed within the carrier. A bearing assembly is located between the differential carrier and the differential case and allows the differential case to rotate within the differential carrier. The differential carrier and a cup of the bearing assembly having mating threads allowing relatively easy alignment of the bearing assembly within the differential. A deformable member is attached to the bearing assembly cup and is deformed and inserted into a slot in the differential carrier upon alignment of the bearing assembly to securely position the bearing assembly.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to vehicle differentials and, in particular, to adifferential and method for assembling a differential that enablesrelatively easy alignment and secure positioning of bearings within thedifferential.

2. Discussion of Related Art

Differentials are provided on vehicles to divide power provided at twooutputs. A wheel differential enables a pair of wheels on a commonrotational axis to rotate at different speeds while the vehicle isturning. A conventional differential includes a differential carrierthat receives a power transmission shaft having a pinion gear mounted atone end. The pinion gear is disposed within the differential and mesheswith a ring gear that is coupled to, or integral with, a differentialcase. The case supports a plurality of bevel gears that transmit torqueto a pair of axle half shafts that are in turn coupled to acorresponding pair of wheels.

The differential case is supported for rotation within the differentialcarrier by a pair of bearing assemblies. During assembly of thedifferential, each of the bearing assemblies must be properly aligned bymoving the bearing assembly axially inward and outward along the axis ofrotation. Conventional bearing assemblies are typically positioned andaligned within the differential carrier using threaded bearing adjustersthat urge the bearing assemblies axially inward and outward. Bolts,clips, cotter pins or metal stampings are used to maintain the positionof the bearing adjusters within the differential once a predeterminedalignment position is reached. This configuration has a significantdisadvantage. The bearing adjusters typically have a finite number oflugs (e.g., twelve to sixteen) projecting therefrom. The bolts, clips,cotter pin or stampings are inserted into one of the lugs or in betweena pair of lugs to retain the bearing adjuster in place. As a result, thebearing adjuster, and therefore the bearing assemblies, can only assumecertain angular and axial positions thereby limiting the ability tooptimally align the bearing assemblies within the differential.

The inventors herein have recognized a need for a differential andmethod of assembling a differential that will minimize and/or eliminateone or more of the above-identified deficiencies.

SUMMARY OF THE INVENTION

The present invention provides a vehicle differential and a method forassembling a differential.

A differential in accordance with one aspect of the present inventionincludes a differential carrier disposed about a first axis and adifferential case disposed within the differential carrier. A bearingassembly is disposed about the first axis between the differentialcarrier and the differential case. The bearing assembly allows thedifferential case to rotate within the differential carrier. Thedifferential carrier includes a first plurality of threads disposed on aradially inner surface. The bearing assembly includes a cup having asecond plurality of threads disposed on a radially outer surface thatare configured to engage the first plurality of threads.

A differential in accordance with a second aspect of the presentinvention also includes a differential carrier disposed about a firstaxis and a differential case disposed within the differential carrier. Abearing assembly is again disposed about the first axis between thedifferential carrier and the differential case to allow the differentialcase to rotate within the differential carrier. The differential furtherincludes a deformable member coupled to a cup of the bearing assembly.At least a portion of the deformable member is deformed and insertedinto a slot in the differential carrier upon alignment of the bearingassembly within the differential carrier.

A method of assembling a differential in accordance with the presentinvention may include the step of providing a differential carrier and adifferential case disposed within the differential carrier wherein thedifferential carrier and the differential case are disposed about afirst axis and the differential carrier has a first plurality of threadson a radially inner surface. The method may further include the step ofinserting a bearing assembly between the differential carrier and thedifferential case wherein the bearing assembly includes a cup having asecond plurality of threads disposed on a radially outer surface andconfigured to engage with the first plurality of threads on thedifferential carrier. The method further includes the step of rotatingthe bearing assembly until a predetermined alignment position isreached. The inventive method may also include the steps of affixing adeformable member to the cup of the bearing assembly, deforming at leasta portion of the deformable member after reaching the predeterminedalignment position, and inserting the at least a portion of thedeformable member into a slot in the differential carrier.

A differential in accordance with the present invention is advantageous.The bearing assembly between the differential carrier and differentialcase may be rotated to align the bearing assembly and may assume aninfinite number of angular positions and axial positions providinggreater control of alignment than in conventional differentials. Thedeformable member provides a relatively inexpensive method of securingthe position of the bearing assembly upon alignment of the bearingassembly within the differential.

These and other advantages of this invention will become apparent to oneskilled in the art from the following detailed description and theaccompanying drawings illustrating features of this invention by way ofexample.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial cross-sectional view of a differential in accordancewith the present invention.

FIG. 2 is perspective view of a bearing cup and deformable member of thedifferential of FIG. 1.

FIG. 3 is a cross-sectional view a bearing cup and deformable member ofthe differential of FIG. 1.

FIG. 4 is a perspective view illustrating engagement of a carrier anddeformable member of the differential of FIG. 1.

FIG. 5 is a block diagram illustrating a method for assembling adifferential in accordance with one embodiment of the present invention.

FIG. 6 is a block diagram illustrating a method for assembling adifferential in accordance with another embodiment of the presentinvention.

DETAILED DESCRIPTION OF ONE OR MORE EMBODIMENTS OF THE INVENTION

Referring now to the drawings wherein like reference numerals are usedto identify identical components in the various views, FIG. 1illustrates a differential 10 in accordance with the present invention.Differential 10 is provided for use in vehicles to enable a pair ofwheels on a common rotational axis to rotate at different speeds.Differential 10 may include a differential carrier 12 that receives apower transmission shaft 14, a pinion gear 16, a ring gear 18, adifferential case 20, a differential spider 22, a plurality of bevelgears 24, 26, 28, 30, and axle half shafts 32, 34. Differential 10 mayalso include bearing assemblies 36, 38 in accordance with one aspect ofthe present invention and may further include deformable members 40, 42in accordance with another aspect of the present invention.

Carrier 12 houses, provides supports for, and maintains the relativeposition of, the other components of differential 10. Carrier 12 may bemade from conventional metals and metal alloys such as steel and isconventional in the art. Carrier 12 may include several members coupledtogether using conventional fasteners (not shown). These members mayinclude, but are not limited to, forward member 44 and bearing caps 46,48. Members 44, 46, 48 of carrier 12 together define a pair of openings52, 54 disposed about an axis 56 of rotation for axle half shafts 32, 34and through which shafts 32, 34 extend. Carrier 12 also definespluralities of threads 58, 60 on at least a portion of the radiallyinner surfaces of members 44, 46, 48 that define openings 52, 54.

Shaft 14 transfers torque from a drive shaft (not shown) to pinion gear16 and is conventional in the art. Shaft 14 is disposed about an axis 62of rotation that extends generally perpendicular to axis 56. Shaft 14 issupported for rotation within member 44 of carrier 12 by a pair ofbearing assemblies (only one of which is partially visible in FIG. 1).

Pinion gear 16 transfers torque from shaft 14 to ring gear 18. Piniongear 16 may be made from conventional metals and metal alloys and maycomprise a hypoid gear. Gear 16 rotates about axis 62. Gear 16 isdisposed about shaft 14 and may be integral therewith as shown in theillustrated embodiment or may be mounted thereto using a conventionalspline connection or in other ways customary in the art.

Ring gear 18 is provided to transfer torque from pinion gear 16 to case20 and is conventional in the art. Ring gear 18 may also be made fromconventional metals and metal alloys and may also comprise a hypoidgear. Gear 18 is affixed to case 20 or may be integral therewith and isdisposed about axis 56.

Case 20 is provided to house spider 22 and bevel gears 24, 26, 28, 30and to transfer torque to bevel gears 24, 26, 28, 30. Case 20 isconventional in the art and may be made from conventional metals andmetal alloys. Case 20 includes first and second members 64, 66 that arecoupled together using fasteners such as bolts or in other wayscustomary in the art. Case 20 is disposed within carrier 12 and, inparticular, within openings 52, 54 of carrier 12. Case 20 is alsodisposed about axis 56 and is supported for rotation about axis 56relative to carrier 12 by bearing assemblies 36, 38.

Spider 22 provides a mounting arrangement for bevel gears 24, 26 and isconventional in the art. Spider 22 is coupled to case 20 for rotationtherewith and supports at least two bevel gears 24, 26 that rotate withspider 22.

Bevel gears 24, 26, 28, 30 are provided to divide and transfer torquebetween axle half shafts 32, 34. Gears 24, 26, 28, 30 are conventionalin the art and may be made from conventional metals and metal alloys.Gears 24, 26 are mounted on spider 22 for rotation with spider 22. Gears28, 30 are mounted on axle half shafts 32, 34 for rotation with shafts32, 34 and rotate in response to rotation of gears 24, 26.

Axle half shafts 32, 34 transfer torque to wheels (not shown) disposedon either side of differential 10. Shafts 32, 34 are conventional in theart and extend outwardly from differential case 20 and carrier 12through openings 52, 54.

Bearing assemblies 36, 38 enable rotation of differential case 20 withincarrier 12. Assemblies 36, 38 are disposed within openings 52, 54 ofcarrier 12 between case 20 and carrier 12 and are disposed about axis56. Each of assemblies 36, 38 may include a cone 68, 70, bearing members72, 74, and a bearing cup 76, 78, respectively.

Cones 68, 70 define a radially inner bearing race and are conventionalin the art. Cones 68, 70 are supported on a radially outer surface ofcase 20 and abut shoulders 80, 82, respectively, formed in case 20.

Bearing members 72, 74 are disposed between cones 68, 70 and cups 76,78, respectively. Members 72, 74 are also conventional in the art andmay comprise tapered roller bearings.

Cups 76, 78 define a radially outer bearing race and are disposed aboutaxis, 56, cones 68, 70 and bearing members 72, 74. In accordance withthe present invention, cup 76, 78 each define a plurality of threads 84,86, respectively, on a radially outer surface. Threads 84, 86 areconfigured to engage corresponding threads 58, 60, on a radially innersurface of carrier 12 to allow movement of bearing assemblies 36, 38within openings 52, 54 inward and outward along axis 56.

Referring now to FIGS. 2-3, deformable members 40, 42 secure theposition of bearing assemblies 36, 38 once assemblies 36, 38 haveattained a predetermined alignment position within differential 10.Although a single deformable member 40 is illustrated in FIGS. 2-3, itshould be understood that members 40, 42 may be identical inconstruction and that the additional description of member 40 set forthherein may be equally applicable to member 42.

Each member 40, 42 may comprise a stamping made from sheet metal or asimilar malleable material and is coupled to a corresponding cup 76, 78of a corresponding bearing assembly 36, 38. Each member 40, 42 may beannular in shape and is disposed about axis 56 upon installation withindifferential 10 (as shown in FIG. 1). Each member 40, 42 is generallyL-shaped in cross-section and has two legs 88, 90.

Leg 88 extends radially relative to axis 56. Leg 88 defines a pluralityof apertures 92 through which fasteners 94 may be used to couple leg 88,and therefore member 40, to a corresponding cup 76 of a correspondingbearing assembly 36. Apertures 92 may be equally angularly spaced aboutleg 88. In the illustrated embodiment, leg 88 includes three apertures92. It should be understood, however, that the number of apertures 92and fasteners 94 used to couple leg 88 to bearing cup 76 may vary.Fasteners 94 comprise pins in one constructed embodiment. It should beunderstood, however, that other fasteners such as dowels, screws,rivets, or bolts may alternatively be used. Member 40 and bearingassembly 36 may be rotated within openings 52, 54 of carrier 12 using atool that grasps one or more fasteners 94. Alternatively, leg 88 maydefine additional apertures 96 configured to receive a spanning toolused to rotate member 40 and bearing assembly 36. Apertures 96 may beequally angularly spaced about leg 88 and each of apertures 96 may belocated midway between a pair of apertures 92, angularly equidistantfrom each aperture 92 of the pair.

Leg 90 extends axially and is perpendicular to leg 88, extending awayfrom cup 76. Upon alignment of bearing assembly 36 within differential10, leg 90 may be deformed by applying a radial force in a radiallyoutward direction on the radially inner side of leg 90 at one or morelocations. Referring to FIG. 4, in this manner one or more portions 98of leg 90 are urged radially outwardly and are inserted into slots 100formed in carrier 12 thereby securing bearing assemblies against furthermovement.

Referring now to FIGS. 5 and 6, methods of assembling a differential inaccordance with the present invention will be described. Each method mayinclude the step 102 of providing a differential carrier 12 and adifferential case 20 disposed within the differential carrier 12 whereinthe differential carrier 12 and the differential case 20 are disposedabout a first axis 56 and the differential carrier 12 has a plurality ofthreads 60 on a radially inner surface. Each method may further includethe step 104 of inserting a bearing assembly 36 between the differentialcarrier 12 and the differential case 20 wherein the bearing assembly 36includes a cup 76 having a plurality of threads 84 disposed on aradially outer surface and configured to engage the threads 60 oncarrier 12. In accordance with one embodiment of the present inventionillustrated in FIG. 5, the method may conclude with the step 106 ofrotating the bearing assembly 36 until a predetermined alignmentposition is reached.

In accordance with another embodiment of the present inventionillustrated in FIG. 6, the method may further include the step 108 ofaffixing a deformable member 40 to the cup 76 of the bearing assembly36. Referring to FIGS. 1-3, member 40 may be affixed to cup 76 using oneor more fasteners 94 extending through corresponding apertures 92, 110in member 40 and cup 76, respectively. The use of member 40 allowsbearing assembly 36 to be rotated in several ways. As describedhereinabove, member 40 may include one or more apertures 96 configuredto receive a tool. Accordingly, the step 106′ of rotating assembly mayinclude the substeps 112, 114 of inserting a tool through one or more ofapertures 96 in member 40 and moving the tool until bearing assembly 36reaches a predetermined alignment position. Alternatively, step 106′ mayinclude the substeps 116, 118 of grasping a fastener 94 coupling member40 to cup 76 of bearing assembly 36 with a tool and moving the tooluntil bearing assembly 36 reaches a predetermined alignment position.

Referring again to FIG. 6, the method may further include the steps 120,122 of deforming at least a portion 98 of deformable member 40 afterbearing assembly 36 has reached a predetermined alignment position andinserting the portion or portions 98 into a slot or slots 100 indifferential carrier 12. Referring to FIG. 5, one or more portions 98 ofleg 90 of member 40 may be deformed and inserted into slots 100 byexerting a radially outward force on leg 90 (e.g., by using a punchingtool).

A differential and method for assembling a differential in accordancewith the present invention offer significant advantages. In particular,the bearing assemblies 36, 38 may be securely positioned in infinitelyvariable angular and axial positions. As a result, the bearingassemblies 36, 38 may be optimally aligned within differential 10. Theinvention also reduces the cost and weight of differential 10 byeliminating the need for separate bearing adjusters.

While the invention has been shown and described with reference to oneor more particular embodiments thereof, it will be understood by thoseof skill in the art that various changes and modifications can be madewithout departing from the spirit and scope of the invention.

We claim:
 1. A differential (10), comprising: a differential carrier (12) disposed about a first axis (56); a differential case (20) disposed within said differential carrier (12); a bearing assembly (36) disposed about said first axis (56) between said differential carrier (12) and said differential case (20), said bearing assembly (36) allowing said differential case (20) to rotate within said differential carrier (12) wherein said differential carrier (12) includes a first plurality of threads (58) disposed on a radially inner surface and said bearing assembly (36) includes a cup (76) having a second plurality of threads (84) disposed on a radially outer surface configured to engage said first plurality of threads (58).
 2. The differential (10) of claim 1, further comprising a deformable member (40) coupled to said cup (76) of said bearing assembly (36), at least a portion (98) of said deformable member (40) deformed and inserted into a slot (100) in said differential carrier (12) upon alignment of said bearing assembly (36) within said differential carrier (12).
 3. The differential (10) of claim 2, further comprising a plurality of fasteners (94) coupling said deformable member (40) to said cup (76) of said bearing assembly (36).
 4. The differential (10) of claim 3 wherein said deformable member (40) is disposed about said first axis (56) and said fasteners (94) are equally angularly spaced about said deformable member (40).
 5. The differential (10) of claim 3 wherein at least one of said plurality of fasteners (94) comprises a pin.
 6. The differential (10) of claim 2 wherein said deformable member (40) is L-shaped in cross-section, having a first leg (88) coupled to said cup (76) of said bearing assembly (36) and a second leg (90) extending perpendicular to said first leg (88) and away from said cup (76) of said bearing assembly (36).
 7. A differential (10), comprising: a differential carrier (12) disposed about a first axis (56); a differential case (20) disposed within said differential carrier (12); a bearing assembly (36) disposed about said first axis (56) and between said differential carrier (12) and said differential case (20), said bearing assembly (36) allowing said differential case (20) to rotate within said differential carrier (12); and, a deformable member (40) coupled to a cup (76) of said bearing assembly (36) wherein at least a portion (98) of said deformable member (40) is deformed and inserted into a slot (100) in said differential carrier (12) upon alignment of said bearing assembly (36) within said differential carrier (12).
 8. The differential (10) of claim 7, further comprising a plurality of fasteners (94) coupling said deformable member (40) to said cup (76) of said bearing assembly (36).
 9. The differential (10) of claim 8 wherein said deformable member (40) is disposed about said first axis (56) and said fasteners (94) are equally angularly spaced about said deformable member (40).
 10. The differential (10) of claim 8 wherein at least one of said plurality of fasteners (94) comprises a pin.
 11. The differential (10) of claim 7 wherein said deformable member (40) is L-shaped in cross-section, having a first leg (88) coupled to said cup (76) of said bearing assembly (36) and a second leg (90) extending perpendicular to said first leg (88) and away from said cup (76) of said bearing assembly (36).
 12. A method of assembling a differential (10), comprising the steps of: providing (102) a differential carrier (12) and a differential case (20) disposed within said differential carrier (12), said differential carrier (12) and said differential case (20) disposed about a first axis (56) and said differential carrier (12) having a first plurality of threads (58) on a radially inner surface; inserting (104) a bearing assembly (36) between said differential carrier (12) and said differential case (20), said bearing assembly (36) including a cup (76) having a second plurality of threads (84) disposed on a radially outer surface and configured to engage said first plurality of threads (58); and, rotating (106, 106′) said bearing assembly (36) until a predetermined alignment position is reached.
 13. The method of 12, further comprising the steps of: affixing (108) a deformable member (40) to said cup (76) of said bearing assembly (36); deforming (120) at least a portion (98) of said deformable member (40) after reaching said predetermined alignment position; and, inserting (122) said at least a portion (98) of said deformable member (40) into a slot (100) in said differential carrier (12).
 14. The method of claim 13 wherein said rotating step (106′) includes the substeps of: inserting (112) a tool through an aperture (96) in said deformable member (40); and, moving (114) said tool until said bearing assembly (36) reaches said predetermined alignment position.
 15. The method of claim 13 wherein said rotating step (106′) includes the substeps of: grasping (116) a fastener (94) coupling said deformable member (40) to said cup (76) of said bearing assembly (36) with a tool; and, moving (118) said tool until said bearing assembly (36) reaches said predetermined alignment position. 